Paraneoplastic NMDA encephalitis, a case report and an extensive review of available literature

Anti‑N-methyl-D-aspartate receptor encephalitis in a 15-year-old girl: a case report

“…These initial signs are followed within 2 weeks by profound neuropsychiatric manifestations, including short-term memory loss, language deficits, delusions, hallucinations, seizures, and disturbed consciousness [4,7,10,11]. Mechanistically, the characteristic psychiatric symptoms are believed to result from NMDA receptor hypo-function, which occurs when autoantibodies bind to the GluN1 subunit of the receptor, leading to its internalization [10,12,13].…”

“…NMDAR encephalitis is a rare paraneoplastic neurological syndrome. Notably, there is an association between NMDAR encephalitis and an underlying neoplastic condition, with approximately 38% of cases linked to ovarian teratomas [2,13]. Ovarian teratomas may contain both mature and immature neuronal tissues that express NMDA receptors, potentially contributing to the synthesis of autoantibodies.…”

“…Ovarian teratomas may contain both mature and immature neuronal tissues that express NMDA receptors, potentially contributing to the synthesis of autoantibodies. These antibodies can then cross-react with NMDA receptors in the neuronal system [7,11,13].…”

“…This overlap of abnormal movements and complex seizures can create clinical dilemmas and lead to misinterpretations, potentially resulting in the unnecessary over-or under-dosing of antiepileptic drugs or other medications used to control dyskinesia. Although the mechanisms behind these phenomena are not fully understood, they are thought to be related to receptor hyperfunction [13].…”